1. Field of Technology
The present invention relates to an apparatus for correcting image distortion and more particularly, to an apparatus and method for correcting image distortion caused by a curved surface of a display panel in a curved display device having a curved display panel and the curved display device including the same.
2. Background
With the development of information society, a display device that may display information has been actively developed. Examples of the display device include a liquid crystal display device, an organic electro-luminescence display device, a plasma display panel, and a field emission display device.
The aforementioned display devices are flat display devices formed in a flat shape. However, the aforementioned flat display devices have been recently developed as curved display devices and commercialized. The curved display device forms a curved display panel that maintains a fixed curvature and provides images with the intensified immersion to viewers.
However, since the curved display device has a bigger change in a viewing angle than the flat display device, a problem occurs in that image is distorted in accordance with a change of a viewing angle.
FIGS. 1A and 1B illustrate an example of images displayed in a flat display device and a curved display device.
Referring to FIGS. 1A and 1B, a first object d1 displayed on a center of a screen of each of a flat display device 10 and a curved display device 20 is moved to one side of the screen and then displayed as a second object d2 or a third object d2′. Since a viewer views the second object d2 or the third object d2′ at a viewing distance longer than a viewing distance of the first object d1 at the center, the viewer feels that the second object d2 and the third object d2′ are smaller than the first object d1. In this case, vertical lengths H of the flat display device 10 and the curved display device 20 are the same as each other, and resolution of the flat display device 10 is also the same as that of the curved display device 20.
At this time, as shown in FIG. 1A, the flat display device 10 displays the second object d2 reduced from the first object d1 at a fixed rate in up/down/left/right directions. However, as shown in FIG. 1B, the curved display device 20 displays the third object d2′ reduced from the first object d1 at an irregular rate in up/down/left/right directions. Therefore, the viewer views the third object d2′ distorted non-linearly.
That is, the curved display device 20 provides images having the intensified immersion to the viewers but displays non-linearly distorted images in horizontal and vertical directions in accordance with a viewing distance and a curvature. This is because that the image input to the curved display device 20 is a flat image taken by a camera of which image pickup surface is a flat surface.
As described above, the curved display device 20 displays a flat image as it is, whereby image distortion is generated at the outside. This image distortion causes inconvenience when the viewer views the curved display device 20.